Add configuration slider for double tapping

source/tap.cpp

@@ -7,42 +7,115 @@
 extern BLEHidAdafruit blehid;
 
 // ─── Tap detection setup ──────────────────────────────────────────────────────
+// REG_TAP_THS_6D bits[4:0] = tapThreshold (1–31); 1 LSB = FS/32 = 62.5 mg at ±2g.
+// REG_INT_DUR2 at ODR=416 Hz:
+//   SHOCK[7:6] = 2 → 38 ms max tap duration
+//   QUIET[5:4] = 2 → 19 ms refractory after tap
+//   DUR[3:0]   = 6 → 115 ms max inter-tap window for double detection
+void applyTapThreshold() {
+  uint8_t thr = cfg.tapThreshold;
+  if (thr < 1)  thr = 1;
+  if (thr > 31) thr = 31;
+  imuWriteReg(REG_TAP_THS_6D, thr & 0x1F);
+}
+
 void setupTapDetection() {
-  imuWriteReg(REG_CTRL1_XL,    0x60);  // ODR=416Hz, FS=±2g
-  imuWriteReg(REG_TAP_CFG,     0x8E);  // INT_EN + LIR + TAP_Z/Y/X
-  imuWriteReg(REG_TAP_THS_6D,  0x0C);  // threshold 750 mg (was 500 mg — too easy to false-trigger)
-  imuWriteReg(REG_INT_DUR2,    0x7A);  // DUR=7(538ms), QUIET=2(19ms), SHOCK=2(38ms)
-  imuWriteReg(REG_WAKE_UP_THS, 0x80);  // enable double-tap
-  imuWriteReg(REG_MD1_CFG,     0x48);  // route taps to INT1
-  Serial.println("[TAP] Engine configured — single=LEFT, double=RIGHT");
+  imuWriteReg(REG_CTRL1_XL,    0x60);  // ODR=416 Hz, FS=±2g
+  imuWriteReg(REG_TAP_CFG,     0x8E);  // TIMER_EN + LIR + TAP_Z/Y/X enabled
+  applyTapThreshold();
+  imuWriteReg(REG_INT_DUR2,    0x62);  // SHOCK=2(38ms), QUIET=2(19ms), DUR=6(115ms)
+  imuWriteReg(REG_WAKE_UP_THS, 0x80);  // bit7=1 → single + double tap both enabled
+  imuWriteReg(REG_MD1_CFG,     0x48);  // route single-tap(0x08) + double-tap(0x40) → INT1
+  Serial.print("[TAP] threshold="); Serial.print(cfg.tapThreshold);
+  Serial.print(" (~"); Serial.print(cfg.tapThreshold * 62.5f, 0); Serial.println(" mg)");
 }
 
 // ─── Tap processing ───────────────────────────────────────────────────────────
-void processTaps(unsigned long now) {
-  // Release held button after CLICK_HOLD_MS
-  if (clickButtonDown && (now - clickDownMs >= CLICK_HOLD_MS)) {
-    blehid.mouseButtonPress(clickButton, false);
-    clickButtonDown = false; clickButton = 0;
+// Only double-tap is mapped to an action. Single-tap is ignored (it always fires
+// before the double is confirmed and cannot be reliably disambiguated on this
+// hardware without an unacceptable latency penalty).
+//
+// The LSM6DS3 sets SINGLE_TAP immediately on first contact — we wait until
+// DOUBLE_TAP is set (within the hardware DUR window of 115 ms) before acting.
+// An additional TAP_CONFIRM_MS guard ensures the TAP_SRC register has settled.
+//
+// IMPORTANT: call mouseButtonPress(bitmask) — single arg only. The two-arg
+// overload takes (conn_hdl, buttons) and sends the wrong button value.
+
+static enum { TAP_IDLE, TAP_PENDING, TAP_EXECUTING } tapState = TAP_IDLE;
+static unsigned long tapPendingMs  = 0;
+static uint8_t       pendingButton = 0;   // 0 = key action pending
+
+// After DOUBLE_TAP fires we add a small settle guard before committing.
+static const unsigned long TAP_CONFIRM_MS = 20;
+
+static void fireTapAction(unsigned long now) {
+  switch (cfg.tapAction) {
+    case TAP_ACTION_LEFT:
+      blehid.mouseButtonPress(MOUSE_BUTTON_LEFT);
+      pendingButton = MOUSE_BUTTON_LEFT;
+      Serial.println("[TAP] Double → LEFT click");
+      statLeftClicks++;
+      break;
+    case TAP_ACTION_RIGHT:
+      blehid.mouseButtonPress(MOUSE_BUTTON_RIGHT);
+      pendingButton = MOUSE_BUTTON_RIGHT;
+      Serial.println("[TAP] Double → RIGHT click");
+      statRightClicks++;
+      break;
+    case TAP_ACTION_MIDDLE:
+      blehid.mouseButtonPress(MOUSE_BUTTON_MIDDLE);
+      pendingButton = MOUSE_BUTTON_MIDDLE;
+      Serial.println("[TAP] Double → MIDDLE click");
+      statLeftClicks++;
+      break;
+    case TAP_ACTION_KEY: {
+      uint8_t keys[6] = {cfg.tapKey, 0, 0, 0, 0, 0};
+      blehid.keyboardReport(cfg.tapMod, keys);
+      pendingButton = 0;
+      Serial.print("[TAP] Double → KEY 0x"); Serial.println(cfg.tapKey, HEX);
+      statLeftClicks++;
+      break;
+    }
   }
-  if (clickButtonDown) return;  // Don't start a new click while one is held
+  clickButtonDown = true; clickDownMs = now;
+  tapState = TAP_EXECUTING;
+}
 
-  // The LSM6DS3 (with D_TAP_EN) already disambiguates at hardware level:
-  //   SINGLE_TAP is only set after the DUR window expires with no second tap.
-  //   DOUBLE_TAP is set immediately when the second tap arrives within DUR.
-  // We trust this directly — no software delay needed.
+void processTaps(unsigned long now) {
+  // ── Release ───────────────────────────────────────────────────────────────
+  if (tapState == TAP_EXECUTING) {
+    if (now - clickDownMs >= CLICK_HOLD_MS) {
+      if (pendingButton) {
+        blehid.mouseButtonRelease();
+      } else {
+        // Key action: release all keys
+        uint8_t noKeys[6] = {};
+        blehid.keyboardReport(0, noKeys);
+      }
+      clickButton = 0; clickButtonDown = false;
+      tapState = TAP_IDLE;
+    }
+    return;
+  }
+
+  // ── Poll TAP_SRC ──────────────────────────────────────────────────────────
   uint8_t tapSrc = imuReadReg(REG_TAP_SRC);
-  if (!(tapSrc & 0x40)) return;  // TAP_IA not set — no event
+  bool tapIA     = !!(tapSrc & 0x40);
+  bool doubleTap = !!(tapSrc & 0x10);
 
-  if (tapSrc & 0x10) {           // DOUBLE_TAP → right click
-    Serial.println("[TAP] Double → RIGHT");
-    blehid.mouseButtonPress(MOUSE_BUTTON_RIGHT, true);
-    clickButton = MOUSE_BUTTON_RIGHT; clickButtonDown = true; clickDownMs = now;
-    statRightClicks++;
-  } else if (tapSrc & 0x20) {   // SINGLE_TAP → left click
-    Serial.println("[TAP] Single → LEFT");
-    blehid.mouseButtonPress(MOUSE_BUTTON_LEFT, true);
-    clickButton = MOUSE_BUTTON_LEFT; clickButtonDown = true; clickDownMs = now;
-    statLeftClicks++;
+  if (tapState == TAP_IDLE) {
+    if (tapIA && doubleTap) {
+      tapPendingMs = now;
+      tapState = TAP_PENDING;
+    }
+    return;
+  }
+
+  if (tapState == TAP_PENDING) {
+    if (now - tapPendingMs >= TAP_CONFIRM_MS) {
+      fireTapAction(now);
+    }
   }
 }